You can do this through the `
EPiServer.Framework.Web.Resources.ClientResource` class and interfaces, to render or inject client resources into content without modifying the templates.
## Define client resource definitions in module.config
The client resource provider finds and returns definitions of client resources, which are defined in manifests of public and protected modules and apps. You can request the definition by name and add it to the page. You do not need a custom client resource provider if you define the resources in [module.config](🔗). The following example shows client resource definitions in a module manifest:
## Implement the custom client resource provider
The client provider class must implement the `
EPiServer.Framework.Web.Resources.IClientResourceProvider` interface and it should be decorated with `
EPiServer.Framework.Web.Resources.ClientResourceProviderAttribute` to register this implementation automatically. In the following example, the sample client resource provider returns one script resource that depends on another client resource provider. The provider resolves the full path to the script file in module directory by module name.
## Require client resources
You can require client resources (often when developing an add-on or plug-in) to render on the page without accessing and changing page templates.
### Implement client resource register
CMS provides the `
EPiServer.Framework.Web.Resources.IClientResourceRegistrator` interface that can be implemented to register client resources for specific rendering area and depends on the current context.
You must execute client resource registers before rendering a page. The code calls register automatically, if templates inherit base classes for Razor pages or controller that are defined in CMS (`
EPiServer.Web.Mvc.RazorPageModel` and `
EPiServer.Web.Mvc.ContentController`). Also, when you request resources for CMS page templates, the resources can inherit the base register class. You should decorate the register implementation class with `
EPiServer.Framework.Web.Resources.RequireClientResourcesAttribute` to make it discoverable automatically.
In the following code example,
RegisterResources` method takes one arguments: the list of required client resources.
Information from current HTTP context can decide which resources are required for this context. Implementation that needs access to current http context should take a dependency to `
The list of required client resources provides the number of `
Require` methods to register required client resources.
You can require a client resource by name if the resource is known and it was defined in any module manifest, or it is returned by custom resource provider. The example register requires two resources by name; these resources were defined in sample module manifest and sample client resource provider.
The third resource was not defined in _module.config_ or provider and this resource is required using its URL in sample register implementation.
See also: `
### Client resource settings
Each Require method returns settings for required client resource to specify an area where you render a resource and filter resources by type.
**Rendering area **
This is a string that identifies the place in templates where you render a resource.
CMS requires two default rendering areas for all templates:
**Header** for resources that you should add inside the <head> tag. You should require styles for this area.
**Footer** for resources that you should add in the bottom of the page, before closing </body> tag. You should put scripts in this area.
You can set rendering area for resource by using `
AtFooter()` methods of client resource settings.
If you do not explicitly specify rendering area, the **Header** is the default option. Sample register requires a style resource without setting the area, so this style is going to be rendered in Header area. **Footer** area explicitly requires two other script resources.
**Filter Resources by Type**
Sometimes several resources of different types are grouped and have the same name. You can request only resources of certain type when you request resources by name. For example, you can define jQuery UI scripts and CSS files using the one name jquery.ui. Then require jQuery UI style resource in the Header area and require scripts in the Footer:
### Request client resources using ClientResources class
Client resource register requires implementation typically when you develop a module and add-on that needs injections.
You can require client resource by using `
EPiServer.Framework.Web.Resources.ClientResources` static class, which provides `
Require` methods with the same signatures as methods in `
IRequiredClientResourceList` interface, if you need to request client resources in code behind or directly in templates. Request resource before you render required resources for corresponding area.
## Render the required client resources
Use HTML helper to render required client resources for a corresponding area. A template must render required client resources at least for two default areas. Render resources for Header area inside <head> tag. Render resources for Footer area in the bottom of the page, before closing </body> tag.
### Web Forms control
EPiServer.Framework.Web.WebControls.RequiredClientResources` control to render required resources in Web Forms templates. The following code renders client resources required for Header area:
### MVC Helper
Use HTML helper extension to render required resources in MVC templates. The following code renders client resources required for the **Footer** area: